Explosively driven fastener having axially collapsible radially expandable locking sleeve



Dec. 1, 1959 R. J. KOPF ETAL 2,914,983

EXPLOSIVELY DRIVEN FASTENER HAVING AXIALLY COLLAPSIBLE RADIALLYEXPANDABLE LOCKING SLEEVE Filed Dec. 9. 1953 l 3 Sheets-Sheet 1 22 v i62O INVENToRs RowLA/vo .1. Kopf YALBERT 7T MASTERS ATTORNEY Dec. 1, 1959KOPF E1' L 2,914,983

EXPLOSIVELY DRIVEN FASTENER HAVING A'XIALLY COLLAPSIBLE RVADIALLYEXPANDABLE LOCKING SLEEVE v Filed nec. 9, 1953 s sheets-sheet 2INVENTORS KOP F ROWLAND J.

ALBERT T. MASTERS BYV ATTORNEY Decl, 1959 R. J. KOPF rs1-AL vEXPLOSIVELY DRIVEN FASTENER HAVING XIALLY COLLAPSIBLE RADIALLYEXPANDABLE LOCKING sLEEvE 3 Sheets-Sheet 3 Filed Dec. 9. 1955 XBX n 26|'cyg /z A e2 vs al eo INVENTUM ROWLAND J. KOPF ALBERT 7'. MASTERS UnitedStates Patent EXPLOSIVELY DRIVEN FASTENER HAVING AXIALLY COLLAPSBLERADIALLY EX- PANDABLE LOCKING SLEEVE Rowland J. Kopf, Rocky River, andAlbert T. Masters, Fairview Park, Ghio, assignornby4 mesne assignments,to Olin MathiesonChemical Corporation, a corporation of VirginiaApplication December 9, 1953, Serial No. 397,198

4 Claims. (Cl. 85-2;4)

This invention relates to fasteners and more particularly to a stud orvbolt of the. type whichis to be driven either through or into wood,metal plate, masonry, concrete or other materials of construction bymeans of an explosive poweredtool.

In the use of' explosive driven fasteners it is often necessary todrive.them into materials or parts of rnaterials not quite capablev of givinga satisfactory hold upon this type of fastener as a result ofpenetration into the bodyof the material. Examples of` such materials,characterized by a certain softness, tendency to spall or splinter, arecertain types of wood, soft aggregate concrete, softV brick or masonry,macadam and even mild steel. The usual explosive driven stud of the typeshown in U.S. Patent No. 1,365,870 will not hold under the leastappreciable pull in some instances in such materials; and often the veryact of screwing a nut down on the threaded end of the fastener willpullit out..

Therefore an object of this invention is the provision of a fastenercapable of not only being driven explosively but of also having animproved holding power ineven those soft materials heretofore'deemedunsuited for explosive driven fasteners.

Another object is'provision of an explosiveI drivenfastener havingenhancedholding power inlanytypeof material with which such fastenershave,I been heretofore found usable so` as to be4 capable of sustaining:heavier loads.

In accordance with this inventionlhere is provided a fastener adaptednot only for facilitating` projectionl of therfastenerwithoutinterference into materials under the action of an explosive but alsofor enabling` subsequent better anchoring of the fastener. Accordinglyafstudsis providedhaving a-suitably pointed front'end'for penetratingthematerial into whichfit is to be-firedandalong., the

shank of the stud back of thepoint aportionfadapted forradialenlargement preferably by expansion or-otherV deformation.

This portion comprisesa sleeve member theV wall of which is deformableat a desired poi-nt southat the wall ofthe sleeve at such point can beexpanded-radially out,- wardly after the fastener or stud hasbeen-driven bymeans of an explosive operated tool intothe mate-rial` ofsome object on which it is desiredto `fastener support other objects.Expansion of the-sleeve is preferably i accomplished by compressionaxially between the point or head of the stud and a compression orscrew-down member or isbrought about with the aid of a wedge.`Infanyevent" the forepart of the shank: of the studfis so 'constructed`as to provide a piercingy form anda shoulderfdesigned to act as anabutment-fortune end` of the expandable portion and-as a protectingcover for the sleeveduring penetration ofthe stud upon itsl being tired.It has beenfound that by providing 4on the` stud a piercingfrhead; or:point having the outermost part of its diameter' not less `than andpreferably slightly-inexcessof the outside diameter of the expandablesleeve at least at and ahead of the deformable section of the sleeve,the stud may be i ce driven very much like the ordinary explosive drivenstud without interference from and disruption of the expandable portion.

The aforementioned objects as well as other objects, advantages, and thespecific nature of the invention will be better understood from thefollowing description of the specific preferred and illustrativeembodiments of the invention shown in the accompanying drawing in which:

Figure 1 is an elevational side View of one embodiment of the article ofthis invention;

Figure 2 is a cross sectional view of the embodiment of Figure l takenon line II-II of Figure 1;

Figure 3 is an elevational rear view of the embodiment of Figure l;

Figure 4 is a sectional view taken on line IV-IV of. Figure 1;

Figure 5 is a view partially in cross section showing a modified form ofcompression member;

Figure 6 is an elevational side view of another'embodiment;

Figure 7 is an elevational side view of a third embodiment havingvarious modifications in the point and sleeve, part of which is brokenaway for clarity;

Figure 8 is an elevational side view of the fastener of Figure 7 afterit has been driven and expanded for full anchorage inthe surroundingmaterial.

Figure 9 is an elevational side View of a fourth embodiment with apartbroken away for clarity;

Figure 10 is an elevational side view of a fifth embodiment, part ofwhich is also shown broken away, employing a wedge;

Figure 11 is` an elevational side` view of still another embodiment ofthis invention shown driven, expanded and serving to attach a channel,for example;

Figure 12 is an elevational side view of another embodiment also'partlybroken away;

nose; Zand a screw-down member 5 threadedly carriedv onthe rearendportion` 4. Sleeve 3 is longitudinally slotted to providea pluralityoff slots S, terminating short: of the, frontend of the sleeve3. Theseslots form a weakened orexpandable regionpreferably in the forepart ofthe sleeve 3 inasmuch as the material of the object' driven' into is`-rleast disrupted" and better suited for anchorage thanparts `locatednearer the surface driven into. A's shown` in Figure 3, the' screw-downmember 5 is adapted toibe turned down on the threaded part 4 and forthispurpose is provided with diametrically opposedl flats Giforengagement with vsome turning instrument as a` wrench. In thisembodiment it is to be noted that, the body'or posterior section 7 ofthe conical point 2 has a diameter in excess of the outside diameterofthe sleeve 3l which leaves a stepped Vabutment 9ybetween section 7and"sl`eeve 3 for the purpose oflpreventingl seizing of the, forepartof" sleeve 3 during firing ,of the fastener and .re- Sultant undesirabledisruptionatthe slots 8.

In operation the fastener of this embodiment is explo- Sivelyf drivenin, the, usual manner and afterward the screw-down member or round nut 5is lturned down to compresstsleeve 3: between-.nut `5 and steppedabutment 9- and cause: the. sleeve to.-expandradial 'at the; slots; 8`until further resistance to turning indicatesV thatftanchor age has beenachieved. There is left protruding the threaded rear end 4 forattachment of some object and load to the fastener after it has been soanchored. Under circumstances where the full length of threaded section4 is desired, the nut 5 may be withdrawn after it has served itsfunction of causing enlargement of the sleeve. In this embodimentfrictional forces between the head 2 and the target material aredepended upon to prevent turning of the shank 1 and the threaded rearend 4 while nut 5 is being turned down.

Another way of obtaining a fully or longer threaded rear end on thefastener is to provide it with the screwdown member of Figure 5 in placeof nut 5 of the foregoing embodiment. This special screw-down is of thesame external diameter as sleeve 3 but has at its front face a recess 11of the same diameter as threaded rear end 4 and internally threaded at12 to a sui'licient depth to permit turning down of the threads 12 onthe threaded rear end 4 for adequate compression and expansion of sleeve3. The rear part of this special nut is shown sol-id except for thediametral hole 14 provided for permitting insertion of a rod for turningto compress the sleeve. However it will be understood that the rear faceof part 10 may instead be provided with a recess in the form of a socketor may be cut to have a square or hexagonal end engageable with a sockethead wrench. In any event the form of screw-down illustrated in Figure 5has external threads 13 for reception of means such as a nut forsecuring objects to the fastener.

rThe embodiment of Figure 6 has back of the conical nose portion 15 andthe cylindrical nose portion 22, a sleeve 16 having helical slots 21instead of longitudinal slots for easier expansion. Back of sleeve 16 isa cylindrical screw-down member 17 screw threadedly carried on the rearend portion 18 of the fastener shank. Both the rear end portion 18 ofthe shank of the fastener and the member 17 are transversely perforated.Hole 19 in 18 is for connection with a tool which will be used toprevent turning of the shank of the stud while hole 20 in 17 isl forengagement with a wrench or the like used to operate the screw-downmember 17. It will be appreciated that this embodiment has particularutility where greater torque is desired to severely deform the sleeve 16at the slots 21 for maximum expansion in material which provides verylittle frictional resistance to undesired rotation of the nose portions15 and 22 during turning down of member 17 under such torque.

The sleeve 16 of the embodiment of Figure 6 is further characterized byan outside diameter a large part of which is substantially identicalwith the diameter of the posterior cylindrical part 22 of the nose.However, at least the front edge of the sleeve is provided with a bevelat 23 which may in some cases be extended as far back as the rearmostpart of the slots 21 so as to avoid inadvertent expansion of the sleeve16 when it is undergoing penetration by explosive power.

The embodiment of Figure 7 also consists of an inner body or shank 24the front of which is provided With an enlarged pointed head 25 and therear end portion 26 which is screw threaded for reception of thecompression member 27. About the intermediate portion of the shank thereis expandable sleeve 28 all of the tubular wall of which, except for aminor portion 29 at the rear and a still smaller connecting band 30 atthe front, is Weakened by helical slots 31 formed therein for obtainingmaX- imum radial enlargement over an extended depth of the penetratedobject with ease. It is to be further observed that the wall thicknessof the sleeve 28 is at a minimum over all and tapers from leastthickness at the connecting band 30 to a greater thickness at theunslotted section 29 where the outside diameter is not less than themaximum diameter of the nose portion and may exceed it slightly. Theembodiment of Figure 7 is further characterized by a nose portion 25having back of the tapered point 32 a cylindrical section 33 of greaterdiameter than part 32 and circumferentially serrated or longitudinallyknurled so as to provide better resistance against rotation of the shank24 during turning of the compression nut 27 than is obtainable byfriction alone. Thus after the fastener illustrated in Figure 7 has beenired, the nut 27 may be turned down to cause sleeve 28 to mushroom atthe slots 31 and make the enlargement 34 which anchors the fastener inthe material 35 as shown in Figure 8 while serrations 33 hold the shankagainst turning and obviate the need for holding the protruding rear endportion 26.

In the embodiment of Figure 9 the inner body or shank of the fastener isprovided at its ends with penetrating head 36 and threaded rear endportion 37. The expansion member 38 and the compression members 39 aremodified. Member 38 is a shortened sleeve having slots 40, eitherlongitudinal or helical although the former are shown, extending fromone end of member 38 to nearly the other end where only a connectingband 41 is left. Member 39 is a sort of extended sleeve internallythreaded at 42 adjacent the rear end of the bore of 39 for screwthreaded engagement with the male threaded portion 37 of the shank. Therear edge of member 39 contains notches or castellations 43 for engagingwith a turning tool such as a spannei wrench for screwing member 39 downto compress member 38 between the rear end of head 36 and the front endof 39 and cause expansion of 38 at the slots 40. This embodiment isadapted for turning compression member 39 down so as not to protrudeabove the surface penetrated by the fastener where it is desired thatonly threaded portion 37, all of it, protrude for connection and fullusage. It also has the advantage of permitting the expandable section tobe made of a soft material such as soft steel while all of the other andparticularly the compressive force transmitting parts may be made of astrong hard steel.

'Fhe embodiment of Figure 10 has an inner body portion in the form of asolid cylindrical shank 44 with a smooth penetrating head 45 at one endand a threaded portion 46 at the rear end pierced by a diametral hole47. Surrounding the shank 44, except for the head 45 and the rear end46, is a sleeve 48 having a circular bore to permit both longitudinaland rotational motion between the shank and the sleeve, an expandablefront part with slots 49 which run from and intersect with the frontface of the sleeve #and having longitudinal serrations 50, i.e. grooves,fins or both, about the remainder thereof. Adjacent and encircling thehead 45 there is a wedge portion 51 for operative engagement with theelongated sectors or ngers formed at the front of sleeve 48 by slots 49for causing expansion of the sleeve as the wedge 51 is forced into theslotted section of sleeve 48 by the act of screwing the shank 46backwardly through sleeve 48 with application of torque by means of asuitable instrumentality inserted at hole 47. It is to be observed thatserrations 50 on sleeve 48 hold the sleeve against rotation thuspermitting turning of the shank with respect to the sleeve. Thisembodiment is peculiarly suited for use where the head is free to movelongitudinally as well as rotationally. Such situation occurs where thehead even with serrations will not hold against rotation dependably aswhere the head passes entirely through the supporting object.

The embodiment of Figure 1l, shown driven through part of an uprightsupporting object 52 with a channel 53 supported thereon and held bymeans of a nut 54 on rear end 55, differs from that of Figure 10 inrespects which adapt it for use where the head 56 provides no hold atall as where it is entirely free from the material into which -thefastener was fired and which will offer little resistance to rotation ofthe sleeve 57. The forepart of the sleeve, as in the previousembodiment, is provided with end slots 58 which permit expansion of thefront of sleeve 57 coacting with the wedge 59 adjacent the exposed head56 so as to positively anchor the fastener. The rear periphery of sleeve57 is in any event provided with 'a suitable number of notches 60 forconnection with Spanner tool in order to either turn or hold the sleeveduring applicationof opposite torques to sleeve 57'and the shank of thefastener at notches 60 and hole 61 respectively after the fastener hasbeen driven explosively.

The embodiment of Figure 12, likethe embodiments of Figures 1.0and 11,is also'characterized by employment of awedge to accomplish expansion.The-fastener shank 62 has a penetrating head-63 having serrated section64 and has a threaded rear end portion 65. On the shank is an expansionsleeve 66 with elongated slots 67 intersecting the rear face of sleeve66. Carried on the shank adjacent sleeve 66 is a screw down sleeve 68,the rearmost end of the bore of which is internally threaded forengagement with threaded rear section 65 and the front of which isconical and forms a wedge 69 for cooperation with the expandable slottedsection of sleeve 66. Application of expansion force to the fastener ofthis embodiment occurs by way of the notches 70 in the rear edge ofsleeve 68.

In Figure 13 there is illustrated a still further modication of thearticle of this invention wherein expansion s obtained by deformation ofa relatively malleable or plastic element in the form of a sleeve orring 71 of lead, synthetic or natural rubber, or of any suitable plasticsuch as polyethylene, for example, and the like carried about the shank72 for compression between the penetrating head 73 and the compressionsleeve section 74 also carried on shank 72. Although the deformableelement 71 is shown unslotted, it will be understood that it may beslotted, if necessary, to even further enhance the expansion effectobtainable with this embodiment.

The fastener of Figure 14 also embodies the fundamental notion of thisinvention but is more suitable for use with installations wherein thefastener is driven through the supporting material so that both endsprotrude and are accessible to the workman and for attachment of loadsto both ends. This embodiment has a shank 75, a special head portion 76for facilitating penetration and also the subsequent provision of a loadholding means on the shank to better resist withdrawal of the fastenerby a force or load applied through the threaded front end 78 or the rearend part 77 integral with shank 75. On the shank there is the threadedanterior protrusion 78 which engages with part of the internal threads79 in the nose portion 76. Slidably mounted on shank 75 between head 76and rear end 77 is an expandable sleeve 80 having slots 81. Expansion isobtained by compressing sleeve 80 by screwing in head 76 relative to theshaft 79 and its threaded rear portion 77. Application of torque to thisfastener is facilitated by provision of a spline 82 or the like on head76 and by provision of the socket recess 83 or the like on the rear end77. Thus after projection this fastener is grasped at both ends bysuitable tools and torque is applied until the sleeve 80 is compressedsufciently to work an expansion at the slots 81 thereby anchoring thefastener. While the rear end 77 is shown as an enlarged section integralwith shaft 75, it will be appreciated that the rear end 77 may be aseparate nut threaded upon shaft 75 similarly to the separable nut-likehead 76 and that the sleeve 75 may be compressed between two nuts atopposite ends of the shank or body 75.

In all the foregoing embodiments the actuating sleeve or screw-downmember, such as member 6 of Figures l to 4, also serves as a means ofretaining the expansion member, such as member 3 upon the shank 1,during handling of the fastener before driving as Well as during drivingof the fastener. In a sense, therefore, another modification of thefastener of this invention is attained by elimination of the screw-downmember and replacement thereof with an expansion member retaining meanssuch as a protruding circumferential upset or enlargement or even a burrformed on the shank back of the expansion member after assembly of theexpansion member on the shank in such a way as to permit compressiveforce to be applied to the expansion member. With this` modificationexpansion. may be worked either` by Iblows appliedV through a Spannersleeveinserted over the rear end ofthe shank or by a screw jack toolapplied over fands engaging with the threaded rear end of the fastener.It will be appreciated, however, that the inclusion. of thecompressionor screw down member is preferredinasmuch this forms a shield againstthe explosion force applied back of this type of fastening device andprevents undesired enlargement of the fastener' during the drivingoperation by such force of explosion acting upon the deformable member.It will also be appreciated that as a further modication the rear endportion of certain of the foregoing embodiments may be of enlargeddiameter so as to operate per se as an object holding or securing meansin the nature of a nail head.

Since other combinations of the various features de- V scribed hereinand even other embodiments of this invention may occur to those skilledin the art, it is to be further understood that the foregoing isintended by Way of illustration of preferred embodiments and not as alimitation of the scope of the present invention except as set forth inthe appended claims.

What is claimed is:

1. A fastener adapted to be driven from an explosive operated toolcomprising an elongated cylindrical shank one end of which is threaded,a pointed piercing head portion of the projectile type described on theother end of said shank for penetrating the surface of a supportingobject under the force of an explosive charge, a compression memberscrew threadedly carried on the first end of said shank and a tubularsleeve surrounding the intermediate.. portion of said shank between saidhead portion and compression member, said intermediate portion of theshank having a diameter less than the maximum diameter of said head andforming with the head at the junction therewith an annular shoulder,said sleeve `having a diameter not in excess of the maximum diameter ofsaid head and being provided with longitudinally extending slots wherebythe slotted portion is weakened and is adapted for expansion after thedriving operation by turning of the compression member down against thesleeve in abutment with said shoulder.

2. A fastener adapted to be driven from an explosive operated toolcomprising an elongated cylindrical shank one end of which is threaded,a pointed piercing head portion of the projectile type described on theother end of said shank for penetrating the surface of a supportingobject under the force of an explosive charge, a compression memberscrew threadedly carried on the first end of said shank and a tubularsleeve surrounding the intermediate portion of said shank between saidhead portion and compression member, said intermediate portion of theshank having a diameter less than the maximum diameter of said head andforming with the head at lthe junction therewith an annular shoulder,said sleeve having a diameter not in excess of the maximum diam- -eterof said head and being longitudinally slotted intermediate the ends ofsaid sleeve whereby the slotted por tion is weakened and is adapted forexpansion after the driving operation by turning of the compressionmember down against the sleeve in abutment with said shoulder. 3. Thefastener of claim 1 wherein the slots are helical. 4. The fastener ofclaim 2 wherein the slots are adjacent the front end of the sleeve.

References Cited in the file of this patent UNITED STATES PATENTS1,164,322 vearman Dec. 14, 1915 1,224,926 Hindmarsh May 8, 19171,232,274 Gay July 3, 1917 1,342,201 Beckwith June l, 1920 (Otherreferences on following page) 8 Catlin Dec. 22, *1953 Murphy May 8,1956'l FOREIGN PATENTS Great Britain 1938 Great Britain Feb. 25, 1948Great Britain Nov. 24, 1948 Australia July 21, 1950

